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351.
Variables related to aggression were explored in a population of psychiatrically disturbed male adolescents in a residential treatment setting. The Marlowe-Crowne Social Desirability Scale, Daydreaming Questionaire, Byrne Repression-Sensitization Scale, and the Buss-Durkee Hostility Inventory were administered to high and low aggressive patients. Multivariate analyses of the data indicated that high aggressors were significantly lower in their social desirability needs and significantly higher in their daydreaming, hostile, attitudes and sensitization than were low aggressive patients. These findings were discussed relative to a greater understanding of aggression in emotionally disturbed adolescents and implications for treatment.  相似文献   
352.
From 1987 to 1989 a campaign to promote the early detection of cutaneous malignant melanoma was conducted in the areas of seven health authorities in England and Scotland (total population 3.6 million). Data were collected on 17,155 patients attending pigmented lesion clinics (PLCs) in each study area during the campaign. After a dramatic rise in PLC referral rates in the first month of the campaign the average monthly referral rate among the target population in the study period settled to an average of 13 per 10(5), a twofold increase compared with the pre-campaign period. Over 85% of patients at all PLCs were seen within 4 weeks of referral from their general practitioners. The melanoma to non-melanoma detection ratio was (1:33). The organization of future early detection initiatives needs careful review and planning, in order to improve their effectiveness in all sections of the population, and to enable health services to cope with the increased work-load.  相似文献   
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Sleep apnea is worse in the supine posture and is associated with retropalatal airway narrowing or occlusion. We have, therefore, examined the effects of posture, negative pressure, and route of respiration on palatal muscle activity in 13 nonsnoring awake male subjects by using electromyography. Electromyographic activity of the levator palatini and palatoglossus was expressed as a percentage of maximum activity. Both the levator palatini (P = 0.002) and palatoglossus (P = 0.002) exhibited phasic inspiratory activity. Overall, posture did not affect the levator palatini (F = 1.58; P = 0.23) or palatoglossus (F = 0.98; P = 0.34) activity, but analysis by route of respiration showed the palatoglossus to be more active when the subjects were nose breathing supine (F = 6.64; P = 0.02). Levator palatini activity was lower when nose breathing was compared with mouth breathing in both the erect and supine postures (F = 6.67; P < 0.02). Nose breathing with the mouth held open caused an increase in palatoglossal activity (P = 0.04). Negative-pressure application (0 to -12.5 cmH2O) caused significant increases in levator palatini (P < 0.001) and palatoglossus (P < 0.001) activity, 100 ms after pressure stimulus, irrespective of route. However, the palatoglossus required significantly greater negative pressures to cause activation when applied via the nose compared with the mouth (P < 0.05). These observations indicate that the levator palatini and palatglossus have respiratory activity and are reflexly activated by negative pressure.  相似文献   
356.
The NH2- and COOH-terminal sequence of nuclear portein A24 has been determined by automatic Edman degradation and carboxypeptidase A and B digestion. Protein A24 is of interest because it is composed in part of histone 2A (Goldknofp, I.L., and Busch, H., (1975) Biochem, Biophys. Res. Commun. 65, 951-960). The sequence of the first 37 NH2-terminal residues is: Met-Gln-Ile-Phe-Val-Lys-Thr-Leu-Thr-Gly-Lys-Thr-Ile-Thr-Leu-Glu-Val-Glu-Pro-Ser-Asp-Thr-Ile-Glu-Asn-Val-Lys-Ala-Lys-Ile-Gln-Asp-Lys-Glu-Gly-Ile-Pro- This sequence is not homologous to any known histone sequence. It contains regions of internal homology (italics). The COOH-terminal amino acid sequence is the same as that of histone 2A, naely: -His-His-Lys-Ala-Lys-Gly-Lys-COOH.  相似文献   
357.
A conversion of the reaction of two cytoplasmic glycolysis enzymes, phosphoglycerate mutase and phosphopyruvate hydratase, is necessary for sucrose synthesis from pyruvate in leaves of C4-plants in the light, when phosphoenolpyruvate synthesis from pyruvate and phosphoglycerate reduction can be carried out by chloroplasts. Leaves of C4-plants differ from those of C3-plants in a higher activity of cytoplasmic glycolysis enzymes, which are distributed irregularly in two assimilatory tissues. The ratio of pyruvate kinase and enolase reaction activities is high in parenchyma linings of vascular fascicles (where mitochondria are concentrated), and it is low in mesophyl tissue, where phosphoglucerate in equilibrium phosphoenolpyruvate reaction is included into photosynthetic metabolism. The data obtained on isolated mesophyl protoplasts have shown that the reaction equilibrium is sharply shifted into the direction of phosphoenolpyruvate formation from phosphoglycerate. However, the incorporation of 14C into sugars is not completely inhibited in the atmosphere of N2-A possibility of incorporation of tri-carbon fragments into sugars in photosynthesizing leaves via conversion of enolase reaction and via alternative pathways is discussed.  相似文献   
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The differing sensitivities of the gallbladder and pancreas to graded doses of CCK have been claimed as important in normal digestive events. As both secretin and CCK are thought to be released in response to normal feeding, we have reexamined the sensitivities of the gallbladder and pancreas to graded increases of CCK with a constant secretin background. Under such conditions the increase in output of pancreatic trypsin and bile salt occurred simultaneously, the dose-response curves being almost superimposable. Thus, under conditions more closely approaching normal postcibal events, the previously described differing sensitivities of the pancreas and gallbladder were not observed.  相似文献   
360.
BACKGROUND: Hearts harvested from non-heart-beating donors sustain severe injury during procurement and implantation, mandating interventions to preserve their function. We tested the hypothesis that limiting oxygen delivery during initial reperfusion of such hearts would reduce free-radical injury. METHODS: Rabbits sustained hypoxic arrest after ventilatory withdrawal, followed by 20 minutes of in vivo ischemia. Hearts were excised and reperfused with blood under conditions of high arterial oxygen tension (PaO2) (approximately 400 mm Hg), low PaO2 (approximately 60 to 70 mm Hg), high pressure (80 mm Hg), and low pressure (40 mm Hg), with or without free-radical scavenger infusion. Non-heart-beating donor groups were defined by the initial reperfusion conditions: high PaO2/ high pressure (n = 8), low PaO2/high pressure (n = 7), high PaO2/low pressure (n = 8), low PaO2/low pressure (n = 7), and high PaO2/high pressure/free-radical scavenger infusion (n = 7). RESULTS: After 45 minutes of reperfusion, low PaO2/ high pressure and high PaO2/low pressure had a significantly higher left ventricular developed pressure (63.6 +/- 5.6 and 63.1 +/- 5.6 mm Hg, respectively) than high PaO2/high pressure (40.9 +/- 4.5 mm Hg; p < 0.0000001 versus both). However, high PaO2/high pressure/free-radical scavenger infusion displayed only a trend toward improved ventricular recovery compared with high PaO2/ high pressure. CONCLUSIONS: Initially reperfusing nonbeating cardiac grafts at low PaO2 or low pressure improves recovery, but may involve mechanisms other than decreased free-radical injury.  相似文献   
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